Keloids are benign collagenous tumors that develop during an exaggerated wound healing response of the skin. Keloids are often familial, but the exact mode of transmission is unclear. The long-term goal of the proposed work is to identify the gene(s) that predipose individuals to keloids. This will be accomplished using a positional cloning strategy. The first aim is to map the gene(s) using extended multiplex families, and then to identify the mutation(s) by screening the mapped region for polymorphisms that co-segregate with the disease. The immediate goal of this proposal is to identify the chromosomal location of the keloid gene(s), using linkage-mapping protocols in several large African-American families. African-Americans have been chosen because the prevalence of keloids is -20 fold higher in Blacks than in Whites. Preliminary data suggest that keloids may be genetically heterogeneous, making it important to focus on only one ethnic group where it is likely that fewer genes will be involved in the etiology of this disease. Mapping will be accomplished by recruiting subjects from families with multiple keloid formers and screening microsatellite markers for linkage to the disease phenotype. Studies will initially focus on chromosome 14q, where a putative keloid locus has been identified in preliminary studies.